The present invention relates to an image forming apparatus which performs a plurality of functions such as copying function, facsimile function, and printing function.
In recent years, so-called multi-function image forming apparatuses have been developed, each capable of per-forming various functions such as copying function, facsimile function and printing. A multi-function image forming apparatus has a scanner and a printer. The scanner serves in achieving both the copying function and the facsimile function. The printer serves to accomplish the copying function, facsimile function and printing function.
Since one scanner and one printer are used for two functions and three functions, respectively, the multi-function image forming apparatus cannot perform all functions fully and completely. If the apparatus successfully perform one function, it cannot perform the remaining functions as efficiently as is desired. This is inevitably because the functions are achieved most efficiently when the printer and the scanner are controlled in different ways.
Even while set in printer mode, the multi-function image forming apparatus does not print data unless paper sheets of the designated size are available. In other words, the apparatus does not print data on paper sheets of any size other than the designated one. If the data were printed on a sheet of a size different from the designated size, the printed sheet would not look as neat as is desired.
Assume that the multi-function image forming apparatus is set in facsimile mode and that paper sheets of the designated size have run out but paper sheets of a greater size are available in the apparatus. In this case, the apparatus prints the received data on a paper sheet of the greater size. This is because it is more important to visualize the received data than to provide a neat printed sheet.
Such print jobs as described above must be executed in different operating modes. Assume one print job is interrupted because, for example, the paper sheets of the size suitable for this print job have run out. In this case, the other print jobs cannot be executed until the cause of the interruption is eliminated and the interrupted print job is completed.